The present invention relates to a device for mounting a spoke on a wheel rim or hub.
It applies more particularly to the wheels of a bicycle.
The mounting of a spoke on a wheel rim is generally carried out using a nut traversing the wheel rim and screwed around the spoke. This mounting creates a tension in the spoke, and one obtains an assembled wheel of quality when the tension is uniform in all the spokes assembled on the rim. The spoke/nut connection can also be carried out on the level of the hub of wheel.
However, it is known that in such an assembly, the wheel thus assembled receives sudden lateral shocks and forces, which causes the relaxation of the effected spokes and the loosening of the nuts and has as a consequence the appearance of effects known as “sail” and “jump” on the effected wheel. These loosening effects appear more particularly on the rear wheels of a bicycle which have less tightened spokes on the side opposed to the free wheel. These loosening effects thus appear more frequently on the side opposite to that where the pinions are mounted.
To solve these problems of relaxation of the spokes and loosening of the nuts relative to the spokes, various solutions have already been proposed.
There is first of all, the solutions of the handcrafted type specific to each assembler of wheels who uses, according to their experience and the means available, the glue, various resins, tallow . . . .
Some have tried to develop industrial solutions directly at the time of the manufacture of the wheel.
Thus, it is known to stick the nut on the spoke with anaerobic adhesive such as that sold under mark “LOCTITE”. This solution is of a high cost and not very reliable because the polymerization of the adhesive is random and a possible later tension adjustment shears the adhesive and the risk of loosening reappears.
U.S. Pat. No. 6,205,664 shows a nut whose head holds a plastic ring which brakes the threaded end of the spoke screwed in to the nut. This solution is reliable but of a high cost because delicate to effectuate.
U.S. Pat. No. 6,557,946 shows a nut for a spoke in which an encapsulated adhesive is placed in the part opposite to the head and which also brakes the threaded end of the spoke screwed in to the nut. This solution is also of a very high cost, which leaves it applicable to the top-of-the-line wheels. Moreover as the solution of joining seen above, it does not allow multiples readjustment without shearing of the adhesive.
Lastly, patent FR2801247 shows a nut deformed locally by a punch, which locally crushes at the same time the thread of the nut and that of the rod of spoke. This solution is not reliable because the local deformation is too weak to obtain a satisfactory braking in the tolerance range of thread screw/nut thread.